NEVER allow a third party to register your domain name for you. Whoever registers a domain name becomes the registrant and OWNER of that domain name. It's as important as filing your DBA!
Don't be fooled by a company offering you a domain name along with a website package. Always insist on registering your own domain name yourself. A hosting company should be able to host any unique domain name. If not, go elsewhere! PERIOD!
You should always list yourself as the administrative contact, billing contact and any other authoritative contact for your domain name so all important information is directly sent to you when it's time to renew or update your records.
Always write down your domain name username and password and keep it in a safe, secure place.
NEVER - NEVER - NEVER give anyone access into your domain name account. There isn't anything hard about managing your domain name records. Always take responsibility for your domain records yourself.
If you should change your contact email address, update your domain name contact information immediately. Registrar's use your email address to contact you in order to send you renewal notices. Keep good records of when your domain name is due to expire. It is best to renew your domain name at least one month before the deadline.